Ratchet wrenches have long been utilized to apply torque, to tighten or loosen a nut or bolt head. Socket wrenches were initially created to rotate the ratcheting head in only one direction. To use a socket wrench in the opposite direction, the ratcheting head had to be removed from the socket or nut, turned over, and reinserted over the socket or nut.
The improved and more complex wrench designs which followed included a device which allowed changing the direction of the ratcheting action without the need to remove the ratcheting head from the socket or nut. Usually, this is accomplished by turning a knob located on top of the ratcheting head, or pushing a knob located on the forward end of the handle.
Most prior art ratcheting wrenches with reverse capabilities employ a rotatable driver which operates a driving pawl with one to four teeth that engage the teeth of the driver. The rotating motion of the driver is transferred to the socket or nut in the desired direction. The reverse oscillation of the handle is transferred to the ratcheting motion of the driver, without engaging the socket or nut. This ratcheting mechanism also eliminates the need to turn the handle and the ratcheting head 180.degree. to engage the socket or nut in the opposite direction. A disadvantage of socket wrenches that use a pawl is the limited torque transferred from the handle to the rotating head and subsequentially to the socket or nut. To increase the torque of this type of socket wrench it is necessary to use longer teeth on the drive head and a correspondingly larger pawl. This change increases the overall dimensions of the wrench, which is counter-productive to the utility thereof.
A search of the prior art did not disclose any patents that read directly on the claims of the instant invention, however the following U.S. patents are considered related:
______________________________________ U.S. Pat. No. INVENTOR ISSUED ______________________________________ 5,152,196 Garrett 6 October 1992 5,095,781 Blake et al 17 March 1992 4,939,961 Lee 10 July 1990 4,602,534 Moetteli 19 July 1986 4,479,409 Antonius 30 October 1984 4,270,417 Tesoro 2 June 1981 2,697,370 Brooks 21 December 1954 1,494,513 Stewart et al 20 May 1924 145,399 Colbert 9 December 1873 ______________________________________
The Garrett U.S. Pat. No. 5,152,196 discloses a ratchet wrench with an auxiliary ratcheting mechanism and a knob-like body. The auxiliary mechanism attaches to a ratchet wrench allowing a loose nut to be tightened by hand prior to using the wrench handle or when no space is available, to move the handle.
The Blake U.S. Pat. No. 5,095,781 discloses a ratchet spinner that is formed as a central aperture disc with a serrated peripheral edge. An integral segmented collar surrounds the aperture in the disc and protrudes axially with a number of flanges that fit into a ratchet wrench. The spinner may be manually rotated in order to ratchet the wrench to tighten the workpiece by hand before oscillating the handle.
The Lee U.S. Pat. No. 4,939,961 discloses a reversible wrench having a first gear face disc with a central square hole and a second gear face disc. The two disc's are meshed by depressing an undulated spring washer axially bound between the discs and the wrench body. A driving stud is positioned within the square hole of a second gear body. To change directions of the ratchet, the wrench must be removed, rotated 180.degree. and reinserted into the socket or nut. The transfer of the oscillating power from the handle to the workpiece provides the power needed for a standard socket, however, the Lee design produces a wrench that:
a) requires a considerable number of moving parts, which reduces the transferred power, PA1 b) creates an added risk of mechanical breakdown, PA1 c) increases the manufacturing process and unit cost, PA1 d) has gear teeth that may "jump" over the engaged teeth because of insufficient spring pressure or too much ratcheting power, and PA1 e) allows only the use of standard sockets. PA1 a) creates a simple and mechanically efficient socket wrench whose principle can be used for either a reversible, or a bidirectional system, PA1 b) can be used directly on a nut or bolt without requiring an additional socket, PA1 c) includes the option to use a special socket, which allows the bolt to penetrate through the socket and wrench, PA1 d) includes an improved adapter which allows the use of standard sockets, and the transfer of increased ratching power to the socket, PA1 e) uses a relatively small number of components, allowing for a reduced dimension of the wrench, PA1 f) accepts the use of a special ergonometrically designed handle, and PA1 g) allows the handle to be rotated 180.degree., for use by either a right or left handed person.
The Moetteli U.S. Pat. No. 4,602,534 discloses a pair of pawls that intersect internal ratchet teeth which are engaged by an annular reversing plate positioned above the pawls. The pawls are jammed between the teeth and the head transfers the torque therethrough.
The Antonius U.S. Pat. No. 4,479,409 discloses an open-end ratchet wrench with a handle joined to a crescent shaped head. A jaw is located within the head and is removed by axial displacement. Spring biased indents and detents resist axial displacement with the ratcheting interposed between the jaw and head.
The Tesoro U.S. Pat. No. 4,270,417 discloses a removable socket of cylindrical shape with circumscribing teeth and a pair of ratcheting keys to lock the movement in an opposite direction. The rotating position is shiftable by a biasing spring mounted in a passage forming structure that presses a ball into alternative circumscribing grooves on the outer wall of the socket.
The Brooks U.S. Pat. No. 2,697,370 discloses a ratchet socket wrench which comprises three separate elements: the ratchet, drive and socket. A limited number of teeth are used in the ratchet and are spaced about the ends. When the handle is rotated in the opposite direction the teeth disengage.
The Stewart U.S. Pat. No. 1,494,513 discloses a wrench utilizing a pawl interfacing with outwardly extending teeth of a socket member. The novelty includes the use of a plurality of socket members slidably and telescopically nested within an outer socket.
The Colbert U.S. Pat. No. 145,399 discloses a wrench that uses a pair of jaws with a bush-thimble inserted in a ratchet barrel with a spring catch. A spring acts to keep the ratchet teeth together and holds the bushing and thimble together.
In summary, the applicant's wrench design differs from the prior art in that the wrench:
For background purposes and as indicative of the art to which the invention is related reference may be made to the remaining cited patents.
______________________________________ PATENT NO. INVENTOR ISSUED ______________________________________ 5,365,807 Darrah et al 22 November 1994 5,295,422 Chow 22 March 1994 5,000,066 Gentiluomo 19 March 1991 4,903,554 Colvin 27 February 1990 4,819,521 Lang 11 April 1989 4,785,495 Dellis 22 November 1988 4,586,307 Parker 20 May 1986 4,520,697 Moetteli 4 June 1985 4,491,043 Dempsey et al 1 January 1985 4,328,710 Shiel 11 May 1982 4,308,769 Rantanen 5 January 1982 4,101,125 Heath 18 July 1978 3,393,587 Jolliff et al 23 July 1968 2,943,513 Gray, et al 5 July 1960 2,651,130 Waterval 8 September 1953 2,300,479 Wilson 3 November 1941 523,850 Cavanaugh 31 July 1894 ______________________________________